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'NITED STATES PATENT OFFICE.

JAMES H. ROOME, OE NE"YORK N, Y.

SI-IEARS.

.Specification of Letters Patent 1\To. 25,140, dated August 16, 1859.

T0 all whom- *Lt may concem:

Be itknown that I, JAMES H.R00ME, of the ciy, county, and State of NewYork, have invented a new and useful Improvement in Tailors and otherShears, which may also be applied to other cutting instruments; andIdo'hereby=deelare that the following is a full, clear, and exactdescriptionof the Same, re'ference being had to the accoinpanyingdrawings, formin'g part of this specification, in which- Figures 1 and 2are opposite-side views 0f a pair of shears constructed aecording to myinvent-ion. Fig. 3 is a top view f the same. Fig. 4 is a transversesection-of the samein the same line m, 00, ofFig. 1.

Similar letters ofreference indieate corresponding parts in the severalfigures.

My invention consists in a certain mode- 0f combining one limb 0f a pairofshears 01' other band outting instrumentwith a handle forming part ofa separate lever and combiningthe said limb and handle With the otherlimb of*the shears whereby the leverage exerted by the thumb or band incutting is gradually increased as the shears cl0se anda drawing cut isproduced.

T0 enable others skilled in the art to make and use my invention I willproceed to describe its construct-ion and operation.

A is the blade, and B, the handle,which combine to form the l'ower limb"0f the shears, made in one piece and of such form that the handle asWell as the blade may rest upon the eutting board 0r table during thecutting Operation. At the junetion 0f the blade and handle this limb ismade much deeper than is common in other shears, in order that the pina, on Which the upper blade works may be arranged some distance abovethe edge of the lower blade.

C, D, is the upper limb made in the f0rm 0f a lever of which the upperblade C, constitutes one arm, and the other arm D, is extended rearwardfrom the said blade and from the point where this limb is attached tothe lower limb by the pin a. This upper limb is made deep eno ugh belowthe point' where it receives the p1n a, t0 reach nearly 130 the bottomof the 1imb A B, as shown in Fig. 1, and below the pin a, it contains aslot b, having the form 0f an arc described from the pin a, said slotreceiving a broad headed screw c, which screws into the 10Wer limb, andthe part 0f the upper limb surrounding the said slot being ratherthicker at that end of the said slot nearest the blade than at theother=end thereof, so that in the closingof the shears the faces of theblades Will be drawn tovvard-each einher er gradually pressed tighteragainst eaeh other. The arm D, contains a slot d, to receive a pin e,Which is carriedby anarm f, which is attached-to the lever.of which theupper handle 0f the shears forme. a part, and whose 'duty Will behereinafter explained.

E, is the upper handle constitutin'g a portion of a 'lever E G, andattached t0 the lower limb of the shears by a fulcrum pin g, which issituatedmuch nearer t0 the front end than tothe rear end whichterminates in the thumb bow. A sl0t h, is-provided in the said leverE-G,for the fulerum pin g, to pass through t0 permit the said handle alongitudinal, as well as a lever=like movement, and the saidpin g, isfitted with an antifriction rollerwithi-n the said slot. The front endof the said lever is connected with the upper limb C D, by a link F, andtwo joint pins 2', j, the pin j, Which attaches the said link to thesaid limb being arranged a little in rear 0f and some distance belowthepin a, and the pin i, which attaehes the said link to the leverE G,being so= arranged that when the shears are closed the said link Will beparallel er nearly so with the edges of theblades. Thearm f,whichhasloeen beforementioned, is attached to the front extremity 0f theleverE G, and standsnp nearly at a right angle t0 the portion 0f the saidhandle that is in front 0f the fulcrum pin g, and the said arm is made0f forked form, as shown in Fig. 4, to receive the arm D, of the upperlimb. The fork 0f the said arm f, also contains a roller 7c, which turnson a pin l, inserted through the said arm; and above the said roller isthe before mentioned pin e, working in the slot in the arm D, of theupper limb. The roller k, works against the bottom of the arm D, of theupper limb, for the purpose 0f forcing up the said arm D, and bringingdown the blade C to effect the cutting operation by the depression ofthe handle E; and the pin e, is for the purpose 0f drawing down the armD, 130 open the shears as the handle E, is raised. T0 provide 'f0r thegrinding away 0f the blades by repeated sharpenings of the shears andinsure the proper closing 0f the shears and their cutting t0 the pointsi when ground away, the arm f, is made detached from the lever E G, and1s secured thereto by a screw m, passing through a s1ot n, in the saidarm and screwing into the said lever E. The s1ot n, permits theadjustment of the said arm f, higher or lower and 130 keep the said armsteady and prevent its being forced out of p1ace by the force applied toit in cutting, there is a steady pin p project-ing from the lever E G,into the said s1ot n, and there are aseries of teeth and notches g g,provided in the said arm, as shown in Figs. 1 and 4, and in the face ofthe 1ever to Which it is attached.

H, is a spring secured to the lower li1nb A B, of the shears, andpressing against an anti-friction roller r, attached to the 1ever E G,for the purpose of raising and throw ing forvvard the rear or lower endof the said lever am]. so opening or assisting in opening the shearswhen the said lever is relieved fro1n the pressure of the thumb or band.

In operating With these shears the lower limb is allowed to rest on theoutting hoard er table; and the cut is produced by depressing the upperhandle, and, at the sa1ne time, pulling or pressing it. in a backwarddirection from the position shown in Fig. 2, and in blaok outline inFig. l. This 1novement of the handle oauses the front end of the lever EG, w'hich is connected with the upper limb to rise, and the arm f, 1301nove backward, and so cause the roller 7c, to pass along the lower edgeof the arm D, of the upper limb, and so depress the upper blade C; but,atthe same time, the end of the 1ink F Which is attached to the risingfront end the lever E G, is raised by the said lever and the said linkis forced bodily ba'ckward by the movernent of the limb C D, and sooaused to force back the said lever bodily on its fulorurn g, thusgradually increasing the length of the said lever behind the said pinand diminishing its length in front thereof,

and so increasing its ower as the b1ade C, descends and While thisincrease of power of the said 1ever is taking place, the roller 70, ingradually receding from the pin a, or fulcrum of the upper 1imb C D, isalso causing the power applied by the said lever to act w'ith increasedeifect 011 the blade, and thus the power exerted by the hand isincreased as the cutting takes place farther from the pin er fulcrum a,and diminishes a greater resistance 110 the' closing of the blades. Thisoperation is illustrated in Fig. l, by the representation 01 the shearsin a closed oondition, in red outline. The operation of the shears isalso greatly assisted by the drawing cut that is caused by the elevatedposition of the pin a.

The sa1ne eonstruction may be adapted, With some advantage, to handpunches, the punch being attached to the lever O D.

VVhat I clai1n as my invention, and desire to secure by Letters Patent,is:

Combining one limb C D, of a pair of shears, or other similarlyoperating band eutting instrument, With its handle E, forming part of aseparate lever E G, and combining the said lirnb and handle with theother 1irnb of t-he shears, by means of an arm f, attached to the saidlever E G, and operating 011 the rear portion D, of the first mentionedlimb, a link F, connecting the said li1nb with the said lever, and amovable fulorum connection g, h, between the said lever and the other1imb; the who1e operating substantially as described -to cause the powerof ehe said lever to inorease as the shears elose.

JAMES H. ROOME.

Witnesses:

J. W. COOMBS, R. S. SPENCER.

